Framed transport header data stored in MessageBuffer

Signed-off-by: Cervenka Dusan <[email protected]>

erpc_c/infra/erpc_client_manager.cpp

@@ -167,7 +167,7 @@ void ClientManager::verifyReply(RequestContext &request)
 
     // Some transport layers change the request's message buffer pointer (for things like zero
     // copy support), so inCodec must be reset to work with correct buffer.
-    request.getCodec()->reset();
+    request.getCodec()->reset(m_transport->reserveHeaderSize());
 
     // Extract the reply header.
     request.getCodec()->startReadMessage(msgType, service, requestNumber, sequence);
@@ -186,13 +186,14 @@ Codec *ClientManager::createBufferAndCodec(void)
 {
     Codec *codec = m_codecFactory->create();
     MessageBuffer message;
+    uint8_t reservedMessageSpace = m_transport->reserveHeaderSize();
 
     if (codec != NULL)
     {
-        message = m_messageFactory->create();
+        message = m_messageFactory->create(reservedMessageSpace);
         if (NULL != message.get())
         {
-            codec->setBuffer(message);
+            codec->setBuffer(message, reservedMessageSpace);
         }
         else
         {

erpc_c/infra/erpc_client_manager.h

@@ -130,8 +130,8 @@ class ClientManager : public ClientServerCommon
 #endif
 
 protected:
-    uint32_t m_sequence;                    //!< Sequence number.
-    client_error_handler_t m_errorHandler;  //!< Pointer to function error handler.
+    uint32_t m_sequence;                   //!< Sequence number.
+    client_error_handler_t m_errorHandler; //!< Pointer to function error handler.
 #if ERPC_NESTED_CALLS
     Server *m_server;                     //!< Server used for nested calls.
     Thread::thread_id_t m_serverThreadId; //!< Thread in which server run function is called.

erpc_c/infra/erpc_codec.hpp

@@ -59,8 +59,7 @@ class Codec
      * This function initializes object attributes.
      */
     Codec(void)
-    : m_buffer()
-    , m_cursor()
+    : m_cursor()
     , m_status(kErpcStatus_Success)
     {
     }
@@ -75,24 +74,28 @@ class Codec
      *
      * @return Pointer to used message buffer.
      */
-    MessageBuffer *getBuffer(void) { return &m_buffer; }
+    MessageBuffer *getBuffer(void) { return m_cursor.getBuffer(); }
 
     /*!
      * @brief Prototype for set message buffer used for read and write data.
      *
      * @param[in] buf Message buffer to set.
+     * @param[in] skip How many bytes to skip from reading.
      */
-    virtual void setBuffer(MessageBuffer &buf)
+    virtual void setBuffer(MessageBuffer &buf, uint8_t skip = 0)
     {
-        m_buffer = buf;
-        m_cursor.set(&m_buffer);
+        m_cursor.setBuffer(&buf, skip);
         m_status = kErpcStatus_Success;
     }
 
-    /*! @brief Reset the codec to initial state. */
-    virtual void reset(void)
+    /*!
+     * @brief Reset the codec to initial state.
+     *
+     * @param[in] skip How many bytes to skip from reading.
+     */
+    virtual void reset(uint8_t skip = 0)
     {
-        m_cursor.set(&m_buffer);
+        m_cursor.setBuffer(m_cursor.getBuffer(), skip);
         m_status = kErpcStatus_Success;
     }
 
@@ -428,7 +431,6 @@ class Codec
     virtual void readCallback(funPtr callbacks1, funPtr *callback2) = 0;
 
 protected:
-    MessageBuffer m_buffer;         /*!< Message buffer object */
     MessageBuffer::Cursor m_cursor; /*!< Copy data to message buffers. */
     erpc_status_t m_status;         /*!< Status of serialized data. */
 };

erpc_c/infra/erpc_framed_transport.cpp

@@ -34,6 +34,12 @@ FramedTransport::FramedTransport(void)
 
 FramedTransport::~FramedTransport(void) {}
 
+uint8_t FramedTransport::reserveHeaderSize(void)
+{
+    return sizeof(FramedTransport::Header::m_crcHeader) + sizeof(FramedTransport::Header::m_messageSize) +
+           sizeof(FramedTransport::Header::m_crcBody);
+}
+
 void FramedTransport::setCrc16(Crc16 *crcImpl)
 {
     erpc_assert(crcImpl);
@@ -47,36 +53,51 @@ Crc16 *FramedTransport::getCrc16(void)
 
 erpc_status_t FramedTransport::receive(MessageBuffer *message)
 {
-    Header h;
+    Header h = { 0, 0, 0 };
     erpc_status_t retVal;
     uint16_t computedCrc;
+    uint8_t offset = 0;
 
     erpc_assert((m_crcImpl != NULL) && ("Uninitialized Crc16 object." != NULL));
 
+    if (message->getLength() < reserveHeaderSize())
+    {
+        retVal = kErpcStatus_MemoryError;
+    }
+    else
     {
 #if !ERPC_THREADS_IS(NONE)
         Mutex::Guard lock(m_receiveLock);
 #endif
 
         // Receive header first.
-        retVal = underlyingReceive((uint8_t *)&h, sizeof(h));
+        retVal = underlyingReceive(message->get(), sizeof(h));
+        static_cast<void>(memcpy(&h.m_crcHeader, message->get(), sizeof(h.m_crcHeader)));
+        offset = sizeof(h.m_crcHeader);
+        static_cast<void>(memcpy(&h.m_messageSize, &message->get()[offset], sizeof(h.m_messageSize)));
+        offset += sizeof(h.m_messageSize);
+        static_cast<void>(memcpy(&h.m_crcBody, &message->get()[offset], sizeof(h.m_crcBody)));
+        offset += sizeof(h.m_crcBody);
 
         if (retVal == kErpcStatus_Success)
         {
+            ERPC_READ_AGNOSTIC_16(h.m_crcHeader);
             ERPC_READ_AGNOSTIC_16(h.m_messageSize);
-            ERPC_READ_AGNOSTIC_16(h.m_crc);
+            ERPC_READ_AGNOSTIC_16(h.m_crcBody);
 
-            // received size can't be zero.
-            if (h.m_messageSize == 0U)
+            computedCrc =
+                m_crcImpl->computeCRC16(reinterpret_cast<const uint8_t *>(&h.m_messageSize), sizeof(h.m_messageSize)) +
+                m_crcImpl->computeCRC16(reinterpret_cast<const uint8_t *>(&h.m_crcBody), sizeof(h.m_crcBody));
+            if (computedCrc != h.m_crcHeader)
             {
-                retVal = kErpcStatus_ReceiveFailed;
+                retVal = kErpcStatus_CrcCheckFailed;
             }
         }
 
         if (retVal == kErpcStatus_Success)
         {
             // received size can't be larger then buffer length.
-            if (h.m_messageSize > message->getLength())
+            if ((h.m_messageSize + reserveHeaderSize()) > message->getLength())
             {
                 retVal = kErpcStatus_ReceiveFailed;
             }
@@ -85,17 +106,17 @@ erpc_status_t FramedTransport::receive(MessageBuffer *message)
         if (retVal == kErpcStatus_Success)
         {
             // Receive rest of the message now we know its size.
-            retVal = underlyingReceive(message->get(), h.m_messageSize);
+            retVal = underlyingReceive(&message->get()[offset], h.m_messageSize);
         }
     }
 
     if (retVal == kErpcStatus_Success)
     {
         // Verify CRC.
-        computedCrc = m_crcImpl->computeCRC16(message->get(), h.m_messageSize);
-        if (computedCrc == h.m_crc)
+        computedCrc = m_crcImpl->computeCRC16(&message->get()[offset], h.m_messageSize);
+        if (computedCrc == h.m_crcBody)
         {
-            message->setUsed(h.m_messageSize);
+            message->setUsed(h.m_messageSize + reserveHeaderSize());
         }
         else
         {
@@ -111,27 +132,32 @@ erpc_status_t FramedTransport::send(MessageBuffer *message)
     erpc_status_t ret;
     uint16_t messageLength;
     Header h;
+    uint8_t offset;
 
     erpc_assert((m_crcImpl != NULL) && ("Uninitialized Crc16 object." != NULL));
 
-#if !ERPC_THREADS_IS(NONE)
-    Mutex::Guard lock(m_sendLock);
-#endif
-
-    messageLength = message->getUsed();
+    messageLength = message->getUsed() - reserveHeaderSize();
 
     // Send header first.
     h.m_messageSize = messageLength;
-    h.m_crc = m_crcImpl->computeCRC16(message->get(), messageLength);
+    h.m_crcBody = m_crcImpl->computeCRC16(message->get(), messageLength);
+    h.m_crcHeader =
+        m_crcImpl->computeCRC16(reinterpret_cast<const uint8_t *>(&h.m_messageSize), sizeof(h.m_messageSize)) +
+        m_crcImpl->computeCRC16(reinterpret_cast<const uint8_t *>(&h.m_crcBody), sizeof(h.m_crcBody));
 
+    ERPC_WRITE_AGNOSTIC_16(h.m_crcHeader);
     ERPC_WRITE_AGNOSTIC_16(h.m_messageSize);
     ERPC_WRITE_AGNOSTIC_16(h.m_crc);
 
-    ret = underlyingSend((uint8_t *)&h, sizeof(h));
-    if (ret == kErpcStatus_Success)
-    {
-        ret = underlyingSend(message->get(), messageLength);
-    }
+    static_cast<void>(memcpy(message->get(), reinterpret_cast<const uint8_t *>(&h.m_crcHeader), sizeof(h.m_crcHeader)));
+    offset = sizeof(h.m_crcHeader);
+    static_cast<void>(
+        memcpy(&message->get()[offset], reinterpret_cast<const uint8_t *>(&h.m_messageSize), sizeof(h.m_messageSize)));
+    offset += sizeof(h.m_messageSize);
+    static_cast<void>(
+        memcpy(&message->get()[offset], reinterpret_cast<const uint8_t *>(&h.m_crcBody), sizeof(h.m_crcBody)));
+
+    ret = underlyingSend(message->get(), message->getUsed());
 
     return ret;
 }

erpc_c/infra/erpc_framed_transport.hpp

@@ -56,6 +56,14 @@ namespace erpc {
 class FramedTransport : public Transport
 {
 public:
+    /*! @brief Contents of the header that prefixes each message. */
+    struct Header
+    {
+        uint16_t m_crcHeader;   //!< CRC-16 over this header structure data
+        uint16_t m_messageSize; //!< Size in bytes of the message, excluding the header.
+        uint16_t m_crcBody;     //!< CRC-16 over the message data.
+    };
+
     /*!
      * @brief Constructor.
      */
@@ -66,6 +74,13 @@ class FramedTransport : public Transport
      */
     virtual ~FramedTransport(void);
 
+    /**
+     * @brief Size of data placed in MessageBuffer before serializing eRPC data.
+     *
+     * @return uint8_t Amount of bytes, reserved before serialized data.
+     */
+    virtual uint8_t reserveHeaderSize(void) override;
+
     /*!
      * @brief Receives an entire message.
      *
@@ -95,13 +110,6 @@ class FramedTransport : public Transport
      */
     virtual erpc_status_t send(MessageBuffer *message) override;
 
-    /*! @brief Contents of the header that prefixes each message. */
-    struct Header
-    {
-        uint16_t m_messageSize; //!< Size in bytes of the message, excluding the header.
-        uint16_t m_crc;         //!< CRC-16 over the message data.
-    };
-
     /*!
      * @brief This functions sets the CRC-16 implementation.
      *

erpc_c/infra/erpc_message_buffer.cpp

@@ -100,15 +100,20 @@ void MessageBuffer::swap(MessageBuffer *other)
     m_buf = temp.m_buf;
 }
 
-void MessageBuffer::Cursor::set(MessageBuffer *buffer)
+void MessageBuffer::Cursor::setBuffer(MessageBuffer *buffer, uint8_t reserved)
 {
     erpc_assert(buffer != NULL);
 
     m_buffer = buffer;
     // RPMSG when nested calls are enabled can set NULL buffer.
     // erpc_assert(buffer->get() && "Data buffer wasn't set to MessageBuffer.");
     // receive function should return err if it couldn't set data buffer.
-    m_pos = buffer->get();
+     m_pos = buffer->get() + reserved;
+}
+
+MessageBuffer *MessageBuffer::Cursor::getBuffer(void)
+{
+    return m_buffer;
 }
 
 uint8_t &MessageBuffer::Cursor::operator[](int index)
@@ -221,8 +226,17 @@ erpc_status_t MessageBuffer::Cursor::write(const void *data, uint32_t length)
     return err;
 }
 
-erpc_status_t MessageBufferFactory::prepareServerBufferForSend(MessageBuffer *message)
+MessageBuffer MessageBufferFactory::create(uint8_t reserveHeaderSize)
+{
+    MessageBuffer messageBuffer = create();
+
+    messageBuffer.setUsed(reserveHeaderSize);
+
+    return messageBuffer;
+}
+
+erpc_status_t MessageBufferFactory::prepareServerBufferForSend(MessageBuffer *message, uint8_t reserveHeaderSize)
 {
-    message->setUsed(0);
+    message->setUsed(reserveHeaderSize);
     return kErpcStatus_Success;
 }

erpc_c/infra/erpc_message_buffer.hpp

@@ -217,8 +217,14 @@ class MessageBuffer
          * @brief Set message buffer.
          *
          * @param[in] buffer Message buffer to set.
+         * @param[in] reserved Moved cursor position outside of reserved memory.
          */
-        void set(MessageBuffer *buffer);
+        void setBuffer(MessageBuffer *buffer, uint8_t reserved = 0);
+
+        /*!
+         * @brief Get message buffer.
+         */
+        MessageBuffer *getBuffer(void);
 
         /*!
          * @brief Return position in buffer.
@@ -368,6 +374,17 @@ class MessageBufferFactory
      */
     virtual MessageBuffer create(void) = 0;
 
+    /*!
+     * @brief This function creates new message buffer with reserved bytes at the beginning
+     *
+     * Reserved bytes can be used by transport to write transport related header file data.
+     *
+     * @param[in] reserveHeaderSize Reserved amount of bytes at the beginning of message buffer.
+     *
+     * @return New created MessageBuffer.
+     */
+    MessageBuffer create(uint8_t reserveHeaderSize);
+
     /*!
      * @brief This function informs server if it has to create buffer for received message.
      *
@@ -382,8 +399,9 @@ class MessageBufferFactory
      * In case of using new buffer function has to free given buffer.
      *
      * @param[in] message MessageBuffer which can be reused.
+     * @param[in] reserveHeaderSize Reserved amount of bytes at the beginning of message buffer.
      */
-    virtual erpc_status_t prepareServerBufferForSend(MessageBuffer *message);
+    virtual erpc_status_t prepareServerBufferForSend(MessageBuffer *message, uint8_t reserveHeaderSize = 0);
 
     /*!
      * @brief This function disposes message buffer.

erpc_c/infra/erpc_simple_server.cpp

@@ -103,7 +103,7 @@ erpc_status_t SimpleServer::runInternalBegin(Codec **codec, MessageBuffer &buff,
 
     if (err == kErpcStatus_Success)
     {
-        (*codec)->setBuffer(buff);
+        (*codec)->setBuffer(buff, m_transport->reserveHeaderSize());
 
         err = readHeadOfMessage(*codec, msgType, serviceId, methodId, sequence);
         if (err != kErpcStatus_Success)

erpc_c/infra/erpc_transport.hpp

@@ -46,6 +46,13 @@ class Transport
      */
     virtual ~Transport(void) {}
 
+    /**
+     * @brief Size of data placed in MessageBuffer before serializing eRPC data.
+     *
+     * @return uint8_t Amount of bytes, reserved before serialized data.
+     */
+    virtual uint8_t reserveHeaderSize(void) { return 0; }
+
     /*!
      * @brief Prototype for receiving message.
      *

erpc_c/setup/erpc_arbitrated_client_setup.h

@@ -66,7 +66,8 @@ extern "C" {
  *
  * @return erpc_client_t Pointer to client structure.
  */
-erpc_client_t erpc_arbitrated_client_init(erpc_transport_t transport, erpc_mbf_t message_buffer_factory, erpc_transport_t *arbitrator);
+erpc_client_t erpc_arbitrated_client_init(erpc_transport_t transport, erpc_mbf_t message_buffer_factory,
+                                          erpc_transport_t *arbitrator);
 
 /*!
  * @brief This function sets error handler function.